The present invention relates to an optical subassembly. More particularly, the optical subassembly of the present invention is provided with planar decoupling.
An optical subassembly is typically configured to be received in a transceiver module and is used to transform optical signals coming from optical fibers to an electrical signal, or to transform an electrical signal to an optical signal. A photodiode, pin diode, or similar optical receiver contained by the optical subassembly transforms the optical signal to the electrical signal and then sends the electrical signal to a processing circuit. A laser diode, pin diode or similar optical emitter contained within the optical subassembly transforms the electrical signal coming from the processing circuit to the optical signal.
The process of converting optical signals to electrical signals and electrical signals to optical signals in a relatively small package produces a significant amount of noise in the conversion process. This generated noise can produce signal denigration if not adequately compensated for or eliminated. Internally decoupling signals using capacitors in the circuitry that converts the signals can be one way of effectively minimizing noise in some instances. If a transceiver is not equipped with such internal decoupling circuitry, however, it is not possible to practically add such circuitry. Also, in some cases such internal decoupling circuitry is not effective to reduce all noise signals. For these and other reasons, there is a need for the present invention.